This is analyzing your palette, look how close some colors are, you are wasting at least 3-4 colors here, and you have only one green

As I told before, I am sure I can do better, but not color waste in this palette, as you see in my graphics, the colors works very well. The dark color for the green is there, works, but not exactly dark green.

Show your proposal color conversion for the entire ingame graphics in 16 colors.

Of course, every person has his own taste, maybe you preffer somethin different color scheme.